After the final whistle, only one undefeated team will be left in the Pac-12. With both schools off to surprising perfect starts, the No. 5 Utah Utes (4-0, 1-0) will host No. 23 California (5-0, 2-0) in Saturday’s potentially conference-shifting matchup at Rice-Eccles Stadium.

Each has steadily risen up the top 25 rankings through the first month and half of the season, but they’ve reached this critical juncture in entirely different ways.

The Golden Bears have forged the nation’s 18th highest-scoring offense with 43.0 points per game, starting with 6-foot-4 junior quarterback Jared Goff. He’s tied for the Pac-12 lead with 15 touchdown passes, and is currently second in passer efficiency at 170.5 with a 70.2 percent completion rate.

Goff and fellow junior receiver Kenny Lawler have connected for eight touchdowns, and Lawler’s well on-pace to shatter his career-season of a year ago with 347 yards off 37 receptions.

Most recently Goff hit Lawler for two of his four touchdowns in Cal’s 34-28 victory over Washington State last week, capped by the Bears 21 third-quarter points.

Cal’s also rolling out the best pass-rushing unit the Pac-12, led by senior defensive end Kyle Kragen. He’s generated four of the Bears 18.0 sacks this season, six more than Washington State’s 12.

But after starting last season 4-1 only to drop six of their final seven games, the Bears are aware of how easily and quickly things can spiral out of control.

“I believe we believed our own hype a little bit,” senior receiver Bryce Treggs told the San Francisco Chronicle. “We started getting complacent a little bit, and we lost that hunger we had the first half of the season.”

Clearly cognizant of what this matchup means for their season and how it could set the table for their first conference title since 2006, the Bears get their first real test against a Utes defense that has punished opponents into submission this season.

The Utes are currently third in the Pac-12 and No. 30 nationally with 18.8 points allowed per game, with opponents netting 10 total touchdowns through four games this season. Furthermore, Utah’s secondary has snatched seven interceptions with sophomore safety Marcus Williams pulling down three, tied for 10 th in the nation.

And Utah already quieted most doubters last week when it roughed up then-No. 13 Oregon 62-20, a win that launched the Utes five spots in the latest national rankings and garnered them seven first-place votes.

The Utes forced three Oregon turnovers, and junior defensive end Pita Taumoepenu recorded two of their 5.0 sacks on the night, while senior quarterback Travis Wilson rifled four touchdown passes and rushed for another 327 total offensive yards on the night.

Though a shoulder injury kept him out of the 45-24 blowout win at Fresno State, Wilson has been on a rolle of late and he might not fret the Bears' pass rush too much. The Utes offensive line has surrendered just one sack all season.